Process of yeast manufacture



Patented Apr. 13, 1926.

UNITED STATES PATENT OFFICE.

JOHN F. 'WBOTEN, OF BALTIMORE, MARYLAND, ASSIGNOB T LIBERTY YEAST COB- PORATION, A. CORPORATION OF MARYLAND.

process or YEAs'r mannr'acrnnn.

No Drawing.

To all whom it may concern:

Be it known that I, Join: F. WnorEN, a citizen of the United States, and a resident of the city and county of Baltimore, State 5 of Maryland, have invented certain new and useful Improvements in Processes of Yeast Manufacture, of which the following is a specification.

This invention relates to yeast manufacture and more particularly to a process in which bone precipitate is employed as an active agent. Among the objects of this invention is the production of yeast by a process, whose cost is materially lower than other roeesses and wherein a large yield of yeast of high quality results.

The nature of mydiscovery and invention will appear from the following description and the claims.

A wort containing, in solution,.nitroge nous material, saccharine matter and mineral salts, is prepared. The wort may include cereal materials, such as rye, barley, malt and sprouts, or such saccharine matter as molasses or b'bth cereal materials and molasses. Grain extracts, which are partly malted, and molasses, preferably beet mo lasses, may be employed, the amount of mo lasses by weight being preferably at least twice as much as the amount by weight of 'ains. Prior to propagation of yeast there- 1 1n, the wort is soured by inoculation with a. lactic'acid culture, preferably to the extent that the acidity of 40 c. c. will require, for neutralization, from c. c. to c. c. of a tenth normal soda solution. After souring, the wort which is of comparatively high Bailing per cent, such as from-8 to 30, is filtered and transferred to a container where stepeofadding bone precipitate to the wort 40 it is'kept 'at a sterilizing temperature,"such as 65 cent. preferably for at least one hour. The wort is then transferred directly to a. fermenterh rphates of alkali metals or p 1 of yeast, containing boneNpreei Before propagation of yeast thereimj v 1 JOH F.

Application filed August 20, 1924. Serial 1N0. 733,194.

part of the wort is diluted to about 1.5? Ball-.

ing and then yeast propagation is commenced, seed ycastbemg added to such diluted portion in a quantity approximately 8 per cent of the total raw materials. Parts of the original wort are added from time to time in accordance with thegrowth requirements ofthe yeast.

In the processes of yeast manufacture which have heretofore been employed, am

monium phosphate has been added to the wort either before or during fermentation to supply phosphorous to the yeast in. amounts varying with the nature of the wort, as is well known in the art. I have discovered that thematerial known in the fertilizer trade as bone' precipitate or precipitated bone phosphate and which is a calcium phosphate compound, produced by the treatment of bone with acid, and the subsequent recipitation of the phosphoric acids with ime, may be very usefully employed in yeast manufacture. Calcinmcompounds and phosphoric acid compounds are necessary to the proper growth of the yeast and also affect the acidity of -the fermenting wort. An analysis of the bone preci 'itate which I have employed is as follows: oisture, dried at 100 cent.5.00%; insoluble siliceous matter-OL26%; di-calcium phosphate C,HPO,2H,O92.5%; mono-calcium phosphate C, (H POQ -2.07

The bone precipitate may be substituted in whole or inpan for ammonium phosphate or for other phosphorus compounds, such as phosphorus acid, phosphoric acid, phos- V of alkali earths.

. \Vhat I claim is: 4

1. In a yeast fermentation process, the

to fermented.

.2. A fermentable solution for the growth itate.

OTEN. 

